1 files changed, 12 insertions, 0 deletions
diff --git a/test/Modules/Inputs/PR20786/random.h b/test/Modules/Inputs/PR20786/random.h
new file mode 100644
index 0000000000000..86a7d83c19c08
--- /dev/null
+++ b/test/Modules/Inputs/PR20786/random.h
@@ -0,0 +1,12 @@
+namespace std {
+  template<typename> struct mersenne_twister_engine {
+    friend bool operator==(const mersenne_twister_engine &,
+                           const mersenne_twister_engine &) {
+      return false;
+    }
+  };
+  struct random_device {
+    mersenne_twister_engine<int> mt; // require complete type
+  };
+}
+